Knitted fabrics for use as a catalytic converter substrate for motor vehicles are known as disclosed for example in U.S. Pat. No. 6,284,201 issued to Buck. Substrates of this type have been found to be very effective and may be configured by rolling or folding the fibrous fabric into various shapes. This type of fabric is reported to have a high mass transfer to the fiber surfaces with a catalytically active material. In addition, it has a bulk elasticity which makes it insensitive to vibrations and pulsations of the gas flow. A round wire is typically used as the strand material for fabric-type catalytic substrates.
While the prior uses of fabric-type catalytic substrates are shown to be effective, there is still a need for greater efficiencies and greater design control of filtration/catalytic performance. There is a further need to provide a catalytic substrate which provides better crush resistance and eliminates dimensional shrinking and provides a higher temperature rating. Furthermore, there is a need to reduce wash coat loss caused by wire chafing and movement between the knitted fibers.